Internal-combustion engine.



H. PIEPER. INTERNAL COMBUSTION ENGINE.

' APPLICATION FIL-ED1UNE 20, 1913..

Patented Sept. 12, 1916.

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mr mwms r-snzns nu. rucmurna, WAsNINGmM n cy H. PIEPER. INTERNAL COMBUSTION ENGINE.

APPLICATION FILED JUNE 20, 1913.

Patented Sept. 12, 1916.

Z SHEETS-SHEET 2 wuss:

HENRI PIEPER, on rnGn, BELGIUM,

InTERnAII-coMBu's'rIoN ENGINE.

Specification of Letters Patent.

Patented Sept. 12, 1916.1

Application filed June 20, 1913. Serial No. 774,857. I

To all whom it may concern Be it known that I, HENRI Pinrnn, a subject of the King of the Belgians, and residing at Liege, Belgium, have invented certain new and useful Improvements in Internal-Combustion Engines; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to' which it appertains to make-and use the same, ref.- erence being had v to the accompanying drawings, and to letters or figures of refer ence marked therein, which form a part of this specificationf i My invention has for its object an explosion or internal combustion engine," in which the admission and theexhaust of the gases are controlled by means of a minimum number of auxiliary regulating devices in such a manner as to effect the moe tion of the auxiliary devices in an extremely simple manner and to render the distribub ing independent of the direction of rotation of the motor, and to assure also the proper working of the gas control system and of the whole engine. To this end according to my invention the gas distribution of a four stroke cycle internal combustion engine is controlled by employing the main piston itself for opening and'closing one or more cylinder orifices serving as passages for the gases and situated toward the end of the stroke, these orifices being connected respec# tively with the inlet or exhaust pipe by means of one or'more suitable auxiliary devices, driven by the engine shaft at half the speed. In this way a four stroke cycle e115 gine is obtained, which has an extremely simple distributing system as regards the form of the controlling devices and their motion. Furtherthis gas distributing sys: tem can be employed for both the directions of running of the engine without any modi} fication. Consequently it allows of dispensing'witlr'tlie complicated reversing mechanisms which are indispensable in the usual constructions of four stroke cycle engines. At the same time the method of working of the engine according to my lnventlon dlffers fundamentally"from"that of the ordinary engines notwithstanding thatall practical requirements are satisfied from both'the mechanical and thermal standpoint. Finally in the case'of 'a-twocylinder four stroke cycle engine my ini' cntion allows of control ling the admission and the exhaust of both the cylinders by meansiof the same auxiliary devices working in series alternately with one or the other of the two main pistons used for opening the cylinder orifices toward the-end'ofthe stroke, the auxiliary devices serving alternately as a distributer for the orifices of on'e orl other, of the two cylinders by connecting these orifices respectively'with the inlet and outlet pipe.

, In the accompanying drawingsz'Figui-e 1 represents'the embodiment of my invention in a 'four stroke cycle engine using the atmospheric pressure for introducing thecharge. Fig. 2 shows the application of my invention'to' a four stroke cycle engine, in which the admission is effected under pressure'produced by a compressor attached to the main piston. Fig; '3 is a longitudinal section of a two cylinder four-stroke'cycle engine embodying my invention. Fig. 4: is a lrorizontal section taken at the level of the cylinder ports ofFig; 3. 1 Fig. 5 is a vertical section taken 3 through the distributing chamber ofiF-ig. '3; Fig. 6 is a crank diagram of the cycle of thetwocylinder engine shown in Figs. 3 to 5'.

Referring'to Fig. 1 the cylinder 1 of the .four stroke cycle engine, in which the piston '2 connected with the motor shaft 5 by connecting rod 3 and crank 4t reciprocates is provided at its lower end with one or more orifices 6 which may be put in communica- 'tion respectively with the exhaust 8 or the inlet 9 by meansof an auxiliary slide piston 11 driven the engine shaft at half speed." The main "piston may be provided with a" nose 12 serving for directing upward the fresh gases on entering in order to produce a better distributing of the charge throughout the cylinder space.

The engine shown in Fig. 1 works in the 1 the cylinder is compressed during the .r'e-1 mainder of the upward stroke and expands "during the following downward stroke; On the other hand this residue of gases is cooled "down during these strokes by the cylinder Walls from their original temperature of about700 to the temperature of the cylinder walls of about 80. the temperature causes a corresponding diminution of the volume of the gas residue. Consequently at the moment where the piston 2 reopens, toward the end of the downward stroke, the Orifice 6, the pressure in the cylinder 1 is considerably below the atmospheric pressure'and the fresh charge of air and fuel is drawn in 'through the orifice 6, which is put in communication at this instant with the inlet 9 by the auxiliary piston approaching now its upper deadpoint. If desired, this suction may be improved by arranging, as. shown in Fig. 1, in the exhaust 8 a ventilator 13 which sucks out a exhaust period.

greater quantity of burned gases during the Evidently any other suit able means may be employed for increasing the exhaust and the vacuum. The introduction of the fresh mixture will be finished,

when the equilibrium is obtained between "the pressures existing respectively in the cylinder and in the inlet pipe approximately at the moment that the main piston 2 on reascending recloses the orifice 6. During the remainder of this upward stroke the mixture is compressed and then ignited, whereafter the cycle recommences. 1

On examining the method of. working of the four stroke .cycle' engine shown inFig. 1, it will be seen that the exhaust and the admission are controlled in a manner differing from the usual four stroke cycle engines. Both the exhaust as well as the inlet take place toward the end of the piston stroke through orifices which are opened and closed by the working piston itself and a single auxiliary device serves only for directing the gases toward the inlet and the exhaust pipe. Consequently a normal rotary crank and reciprocating rod or similar driving mechanisms canbe employed for driving the auxiliary device by the engine shaft at half speed, while in the usual four stroke cycle engines,- using a single gas 'controlling device the driving mechanisms are very complicated in order to obtain the necessary relation of the movement of the auxiliary device tothat of the main piston. Further in the engine represented in Fig. 'l the relation of the motion of the distrib- -uter -piston 11 to that of the main piston 2 may be chosen so that both the pistons arrive at their lower deadpoints at the same moment, thus permitting the use of the distribution'system for, both directions of rotation of the engine without being obliged to provide special reversing devices as in the usual four stroke cycle. engines. This advantage is very useful especially for'driv- Ling vehicles by means of a four stroke cycle explosion engine acting directly upon the wheels so that the engine is able to run in both directions according to the actual sense This reduction of v ipartly expelling the charge drawn in.

of running of the vehicle. The control of the vehicle is thereby considerably simplified .ton works under very favorable mechanical conditions in that only its head surface is exposed to the hot burned gases, its sliding wall being always cooled down. All these advantages are obtained by means of a con.- struction of great simplicity comprising besides the working parts of the engine itself, only a single auxiliary device driven simply by a rotary crank shaft and a reciprocating rod.

It is not absolutely necessary to introduce the fuel, as shown in Fig. 1, through the same cylinder orifice as the combustion air toward the end of the stroke. The fuel may be admitted separately through an orifice independent of the piston, while only the combustion air is introduced through the orifice situated at the end of the cylinder. In this case the fuel is introduced alone or mixed only with the small quantity of air necessary for its vaporization. The valve serving for controlling the fuel admission may be provided, for instance, at the top of the cylinder and be opened automatically by means of the vacuum existing in the cylinder at the end of the suction stroke. The separate introduction of fueland air will be of a special advantage in the case of heavy fuels. Further instead of the orifice shown in Fig. 1, as common for both the admission and the exhaust, one or more orifices for the inlet and one or more other orifices for the exhaust may be provided in the cylinder toward its lower end, the exhaust orifices being preferably arranged above the admission orifices at a convenient distance. In this case the auxiliary piston works in such a manner as to close the admission orifices during the exhaust period and the exhaust orifices during the admission period. ;The separation of the cylinder openings for inlet and exhaust gives the advantage of improving the admission and the exhaust of the .;four stroke cycle engine. In providing only .a cylinder orifice serving for both the enter- -ing and the escaping gases, the same must :be arranged in the cylinder wall at the end of the inward stroke so as to avoid the inconvenience due to the ascending piston ;the other hand a sufliciently long exhaust time requires an orifice opened by the piston jat a sufficient distance from its lower .dead point. proper working may be easily satisfied by These two requirements of providing besides the orifice serving for the .fresh gases, a separate orifice serving only for the escaping gases, which may be situated at a higher level than the inlet orifice or orifices. In the embodiment of my invention shown in Fig. 2 this separation of the inlet and exhaust cylinder orifices and the independent introduction of the fuel are illustrated. Further the four stroke cycle engine according to Fig. 2 is improved by using the main piston for introducing the combustion air under pressure. The admission orifice 17 is arranged in Fig. 2 at the end of the stroke and the exhaust orifice 18 at a convenient distance thereabove. The auxiliary piston 11 driven by the engine shaft 5 at half the speed serves for closing the orifices 17 during exhaust and the orifices 18 during inlet. The working piston 19 has an elongated portion carrying a compressor piston working in the chamber 23. This chamber 23 communicates with the atmosphere through the automatic valve 22. The elongated portion of the piston 19 has an annular groove 20, through which the compression chamber 23 can communicate with the reservoir 25 when the piston 19 is in the upper deadpoint. The receiver 25 is put in communication with the cylinder space through the pipe 26 and the admission orifice 17 when the auxiliary piston 11 approaches its upper deadpoint. The cylinder head carries an automatic valve 21 serving for admitting separately the fuel.

The four stroke cycle engine illustrated in Fig. 2 works in the following manner When the main piston 19 descends after the explosion, air is drawn into the chamber 23 through the valve 22 from the atmosphere by the compressor piston. \Vhen the orifice 18 is opened by the main piston 19, the exhaust begins. At this time the auxiliary piston 11 closes the admission orifice 17 and cuts off its connection with the reservoir 25. During the next stroke, there is compression on the one hand of the gas residue remaining in the cylinder after closing the orifice 18 and on the other hand of the quantity of air drawn in into the chamber 23. Toward the end of this stroke the chamber 23 communicates with the reservoir 25 through the groove 20, so that the quantity of air, compressed in the chamber 23, can enter the res ervoir 25. During the next stroke a new quantity of atmospheric air is drawn into the chamber 23 through the valve 22. Sii'nultaneously in the cylinder spacea vacuum is produced by cooling down the gas residue. This under-pressure may be increased by improving the preceding exhaust by the suction action of a ventilator or by other suitable means. Consequently the valve 21 will be opened and the fuel is drawn in through the small orifice arranged at the cylinder head during the third stroke, the fuel being mixed only with the small quantity of air absolutely necessary to its vaporization. Toward the end of the suction stroke, the pisten 11, approaching its upper deadpoint, cuts oil the connection between the orifice 18 and the exhaust 8 and produces a free passage between the reservoir 25 and the orifice 17. N ow when the working piston 19 opens the orifice 17, the quantity of compressed combustion air, contained in the reservoir 25, can enter the cylinder space where it is mixed with the vapors of the fuel. The valve 21 will be closed and'the fuel admission be finished as soon as the pressure in the cylinder is equal to the atmosphere. The introduction of the combustion air coming from the reservoir 25 will cease, when the pressures in the cylinder and the reser-' voir equalize each other. Nearly at the same time the piston 19 on ascending will close the orifice 17 and then the new charge of air and fuel is compressed. An escape of fresh gases through the orifice 18 is avoided by the piston 11. Toward the end of this stroke the new quantity of air, compressed in the chamber 23, is introduced into the reservoir 25 through the groove 20. The cycle recommences after the explosion of the fresh charge and during the first and the second stroke of this cycle a further quantity of air is sucked in into the chamber 23, compressed there and then forced in into the reservoir 25. In this way on every cycle a quantity of air, corresponding to the double volume of the chamber 23 enters in the cylinder.

The Figs. 3 to 5 show a two cylinder four stroke cycle engine in which the gas distributing system according to my invention is employed. In this case my invention gives the advantage that the gas control of both the cyclinders can be effected by means of the same auxiliary devices putting in communication the orifices of the two cylinders alternately with the inlet and exhaust pipe, the main pistons opening the appertaining cylinder orifices at the proper moment toward the end of the stroke.

In Fig. 3 the two main pistons 31 and 32 moving respectively in the cylinder 33 or 31 and acting upon the engine shaft 35 are shifted relatively to each other through Every cylinder has one or more orifices situated toward the end of the stroke. For instance, as shown specially in Fig. l, two orifices 36 or 37 may be arranged respectively in the cylinder 33 or These gas orifices are put in communication alternately with the inlet 38 and the exhaust 39-see Fig. 4by means of the distributer piston 10, driven at half speed by the shaft appertaining thereto by means of a suitable gearing in a well known manner.

The diagram represented in Fig. 6 gives the relation of the circle of the distributer crank to the cylinder orifices. It is assumed in Fig. 6 the orifices 36 and 37 of the two cylinders 33, 31 are arranged at the same "level and have the same height a, and the distributer 10 is shifted relatively to the main pistons 31, 32' so that its crank is 45 in advance of the exterior deadpoint when in Fig. l or 2.

Distributer 40. Piston 31. Piston 32.

Position A. Upper deadpoint. Lower deadpoint. Communication with Explosion, orifice 36 Exhaust, orifice 37 exhaust 39. closed. open.

Position B Lower deadpoint... Upper deadpoint. Communication with Exhaust, orifice 36 Orifice 37 closed.

exhaust 39. open.

Position C Upper deadpoint Lower deadpoint. Communication with Orifice 36 closed Suction, orifice 37 inlet 38. 7 opened.

Position D Lower deadpoint. Upper gleadpojnt. Communication with Suction, orifice 36 Explosion, orifice 37 inlet 38. open. closed.

The compression of the charge takes place in the cylinder 34: during the stroke CD, in the cylinder 33 during the stroke DA after the closing of the orifice 36 or 37 respectively by the piston 31 or 32. The vacuum necessary for drawing the fresh charge into the cylinder may be produced in the engine shown inFigs. 3 to 5 in the same manner as in the engine illustrated It will be seen that this two cylinder engine has a great simplicity of construction and of Working because besides the working parts of the engine itself only a single auxiliary devicedriven crank and connecting rod is necessary for controlling l the gases of both the cylinders. The phase- .displacement between the cranks of the distributer and the main pistons may have any suitable value. In choosing the phase dis placement shown in the diagram of Fig. 6 there is the particular advantage that the distributing system enables the'two' cylinder engine to run in both directions of rotation without employing the usual reversing devices.

.Having thus described my invention I declare that what I claim as new and desire to secure byLetters Patent is p 1. In a four stroke cycle internal combustion engine the combination with the working cylinder of inlet and outlet passages situated in the cylinder wall toward the end ofthe outward stroke,a reciprocating power piston controlling alone the duration respectively of the admission and thee'xhaust through said passages toward the end of the outward stroke and the commencement of the inward stroke, an inlet pipe, an exhaust pipe, distributing means serving only to complete the way for the gases entering and escaping through said passages respectively toward the inlet and outlet pipe, and mechanical transmission means driving said distributing means at half the speed of the engine.

2. In a four stroke cycle internal combustion engine in combination a working cylinder having orifices situated toward the end of the outward stroke and common for both the admission and exhaust of gases, a power piston controlling alone said cylinder orifices toward the end of the outward stroke and the beginning of the inward stroke, a distributing device putting said cylinder orifices in communication respectively with the inlet or exhaust pipe and mechanical transmission means for driving said distributing device from the engine shaft at half the speed and with a coincidence of the deadpoints of the distributing device and the main piston.

3. In a four stroke cycle internal coni- -bustion engine the combination with the -working cylinder of ports situated toward the end of the outward stroke, a power piston controlling alone the duration of both the admission and the exhaust of the gases entering and escaping respectively through said ports, an inlet pipe, an outlet pipe, distributing devices, putting the cylinder space in communication with the inlet ,pipe and cutting off its communication with -the outlet pipe during the admission period and establishing communication between the cylinder space and the exhaust pipe and cutting off its connection with the inlet pipe during the exhaust period, and mechanical means fOr driving said distributing device :at half speed from the engine shaft.

4. In a four stroke cycle internal comfbustion engine two working cylinders, each having ports situated toward the end of the outward stroke, two power pistons shifted relatively to each other through 130 each -working in one of the two cylinders and controlling alone the duration of the admission and exhaust through said adjacent cylinder ports, distributing means common fto both the cylinders and serving to direct .the gases entering and escaping through said ports respectively of the one and the other of the two cylinders toward the inlet or outlet pipe and mechanical transmission means for driving said distributing means at half the speed of the engine.

5.'In a four stroke cycle internal coinbustion engine in combination two cylinders "each having orifices situated toward the end of the outward stroke and common for both the admission and exhaust of gases, two

power pistons shifted relatively to each other through 180, one working in one of the two cylinders and opening said adjacent orifices toward the end of its outward stroke, the other moving in the other cylinder and opening said adjacent orifices toward the end of its outward stroke, a single distributer device common for both the cylinders and connecting said orifices of the two cylinders alternately with the inlet or exhaust pipe and mechanical transmission means for driving said distributing device at half speed from the engine shaft.

6. In a four stroke cycle internal combustion engine two cylinders each having orifices situated toward the end of the outward stroke and common for both the admission and the exhaust of gases, two power pistons shifted relatively to each other through 180 one working in one of the two cylinders and controlling said orifices appertaining thereto, the other moving in the other cylinder and controlling said orifices appertaining thereto, a single distributing device common for both the cylinders and connecting said orifices alternately with the inlet and the exhaust pipe and mechanical transmission means for driving said distributing device from the engine shaft at half speed and with an angle of lag of 45 relatively to one of the two main pistons.

In testimony whereof I afiiX my signature in presence of two witnesses.

HENRI P PER.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, I). G. 

